linux-kernel - [PATCH 2/3] spi: spi-geni-qcom: Set an autosuspend delay of 250 ms

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Message-Id: <20200701174506.2.I9b8f6bb1e7e6d8847e2ed2cf854ec55678db427f@changeid>
Date:   Wed,  1 Jul 2020 17:45:08 -0700
From:   Douglas Anderson <dianders@...omium.org>
To:     Mark Brown <broonie@...nel.org>, Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>
Cc:     akashast@...eaurora.org, linux-arm-msm@...r.kernel.org,
        mkshah@...eaurora.org, swboyd@...omium.org,
        georgi.djakov@...aro.org, ctheegal@...eaurora.org,
        mka@...omium.org, Douglas Anderson <dianders@...omium.org>,
        linux-kernel@...r.kernel.org, linux-spi@...r.kernel.org
Subject: [PATCH 2/3] spi: spi-geni-qcom: Set an autosuspend delay of 250 ms

In commit 0e3b8a81f5df ("spi: spi-geni-qcom: Add interconnect
support") the spi_geni_runtime_suspend() and spi_geni_runtime_resume()
became a bit slower.  Measuring on my hardware I see numbers in the
hundreds of microseconds now.

Let's use autosuspend to help avoid some of the overhead.  Now if
we're doing a bunch of transfers we won't need to be constantly
chruning.

The number 250 ms for the autosuspend delay was picked a bit
arbitrarily, so if someone has measurements showing a better value we
could easily change this.

Fixes: 0e3b8a81f5df ("spi: spi-geni-qcom: Add interconnect support")
Signed-off-by: Douglas Anderson <dianders@...omium.org>
---

 drivers/spi/spi-geni-qcom.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index bb4cdda2dec8..f51279608fc7 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -595,6 +595,8 @@ static int spi_geni_probe(struct platform_device *pdev)
 
 	init_completion(&mas->xfer_done);
 	spin_lock_init(&mas->lock);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 250);
 	pm_runtime_enable(dev);
 
 	ret = geni_icc_get(&mas->se, NULL);
-- 
2.27.0.383.g050319c2ae-goog